Nonfoaming asphalt saturant



atented June 22,1943

NUNFOAMING ASPHALT SATURANT Henry S. Goodwin, Fanwood, N. .11., assignor, by mesne assignments, to Standard Catalytic Company, a corporation of Delaware No Drawing. Application February 24, 1941, Serial No. 380,311

3 lllairns.

This invention relates to improvements in asphalts employed in saturating materials such as rag felt, asbestos paper, woven fabrics, building boards, etc., and particularly in those asphalts used for such purposes which are solid at ordinary temperatures and are applied in a molten state at elevated temperatures.

In the preparation of asphalt shingles, building boards, and other materials wherein rag felt, asbestos paper, etc., are saturated with asphalt, an elevated temperature of about 400 F. is required. The rag felt or other fibrous material that is used generally contains small amounts of moisture which is difficult to remove without subjecting the material to elevated temperatures for extended periods of time and with attendant loss in the tensile strength of the materials to be treated. On bringing the rag felt containing the small percentages of moisture into contact with the hot asphalt saturant objectionable foaming takes place.

The extent of the foaming is appreciably infiuenced by the amount of moistur brought into contact with the hot asphalt by the temperature It is an object of this invention to prepare an asphaltic material which will not foam excessively and/or will form an unstable (rapidly breaking) foam, when brought into contact with moist materials such as rag felts, etc., at an elevated temperature.

According to this invention the addition of a small amount of sulfonated fatty oil to an asphalt appreciably reduces the stability or tenacity of the foam formed when the heated asphalt and moist materials are brought into contact. I have found that sulfonated animal fats are most suitable and effective, particularly sulfonated tallow.

The asphaltic material that is to be used in saturating the felts, asbestos sheets, etc., employed in the production of asphaltic roofing, building boards, and the like, is first pretreated by the incorporation of small amounts of the sulfonated fats. For example, sulfonated tallow, when introduced into the asphalt in amounts up to 0.20% greatly reduces the tenacity (or lasting quality) of the foam. Pre-treatment of the asphalt in greater amounts than 0.20% of the tallow, on the other hand, causes greater tenacity of the asphalt, and by properties of the asphalt of the foam as shown in the following table:

Effect of sulfonated tallow as a foam depressor for asphalt satumnt Physical I M research lab foam Composition of sample iuksfpgcglois Lvst results Sulfo- Pen. Height of Time to Time to Asphalt used nated S. P. at foam 1st clear total tallow 77 F. rise spot clcarancc Per cent F. Inches Secs. Secs. Venezuelan heavy flux... 0.00 100 170 0 4130 D 0.05 103 160 360 0. 10 105 163 2 330 0.20 103 166 2 as 405 0. 40 103 167 2% 110 l, 020 0.80 102 177 2% 1, 350 1, 850+ l. 60 101 204 c Q l, 750 1, 850+ 0, 00 106 192 2 245 000 0.05 197 2 205 845 0.10 198 2 195 830 0. 20. 105 201 2 190 32:- 0. 40 105 210 2 185 S00 0. 00 106 163 2 462 1, 100+ 0. 05 107 158 l% 320 870 0. 10 107 158 1% 365 1, 090 0. 20 106 154 2% 285 1, 850+ 0. 40 105 151 2% 650 1, 850+ 0.00 106 179 2% 335 1,175 0. 05 104 171 2% 240 815 0. 10 105 173 2% 245 940 0. 20 106 175 2% 210 870 0. 40 106 182 2% 510 1, 850+ which tend to stabilize the foam that is formed. The foaming characteristics appear to be inherent in the asphalt but may be modified by the addition of suitable quantities of such agents as are indicated herein.

Alternately, the addition to asphalt of small amounts of the sodium sulfonate salts of isobutyl phenol derivatives or lauryl amine modifies the foaming properties of the asphalt so that such 6o asphalt, when caused to foam by contact with moisture, does not form a stable or slow breaking foam. The salts found most suitable and effective are the sodium sulfonate salts of tetraisobutyl phenol or of triisobutyl phenol. The sodium sulfonate salt of tetraisobutyl phenol is preferred. The amount of the salt used may be varied from 0.05 to 0.1% in either case.

The asphalt material that is to be used in the preparation of asphalt shingles, building boards, and other materials is first pretreated by the incorporation of the sodium sulfonate salt of one of the isobutyl phenol derivatives. For example, the sodium sulfonate salt of tetraisobutyl phenol, when introduced into the asphalt in amounts up to 0.1% greatly reduces the tenacity (or lasting quality) of the foam. Pretreatment in greater amounts than 0.1% of the salt, on the other hand, may cause greater tenacity of the foam.

The following table illustrates the beneficial effects obtained:

Asphalt used: Colombian 180/200 Pen (01.) flux Sodium sulfonate salt i Agent used Tetra-iso- Tri-iso- None butyl butyl phenol phenol Percent agent added 0.00 0.05 0.10 0.05

Foam test results Height of foam rise 2 /1 2% 2% 3% Time to 1st clearance "seconds" 335 245 285 270 Time to total clearance do 1,175 920 980 325 The additions of small amounts of lauryl amine, 0.02% or more by weight, likewise decreases the foaming action of asphalts.

The following experimental laboratory data illustrate the advantage of using lauryl amine as a foam depressant:

I. ASPHALT FLUX EMPLOYED: 150 s. P. OXIDIZED VENEZUELAN SHINGLE SATURANI Lauryl Soften- Pen Height Retention amine ing time of added point foam Percent F. Inches Seconds None 156 so s5 0. 04 152 30 5% 55 (These blends prepared at 300-350 F.)

II. ASPHALT FLUX EMPLOYED: COLOMBIAN ROOFERS FLUX Lauryl sommin P Retention g en. amine time of added loam Per cent F. Seconds None 102 179 430 0.1 105 180 410 I 0.2 104 182 420 0.4 104 187 370 1.2 103 227 385 (These blends prepared at 250300 F.)

The above data indicate that the maximum foam reduction appears to have been obtained by the addition of 0.4% (or more) of the lauryl amine.

Lauryl amine might also be employed as a foam depressant for other materials such as transformer oils, lubricating oils, quenching oils, etc.

The foaming of the asphalts according to the above tablesv were compared by the following method.

Two hundred grams of the asphalt under test ar heated to 420 F. and grams of this are poured into a thin walled cylindrical copper container open at the top, having an inside diameter of 4%; inches and 11 inches high, with small lugs placed 1 2 /2, 3 5, 6, 7, 8, 9 and 10 inches from the bottom. The container is well lagged on the sides but not on the bottom. The asphalt and container is maintained at a temperature of 400 F. plus or minus 3 F. A sheet of blotting paper, 3 x 3 inches in area, is air dried and moistened with 3.3 ml. of water in such a manner than even saturation of the paper is obtained in approximately 45 seconds. The wet paper is immersed in the hot asphalt'and pushed to the bottom of the container with a stirring rod. Observations are made of the maximum height to which th foam rises, and the period of time from the introduction of the watar-moistened paper until the foam has subsided to the lug placed 2 inches from the bottom of the container, this being the subsidenc time. As the foam subsides the stirring rod is gently run around the edge of the foam in order to promote even subsidence, and to more closely detect the time at which the foam reaches the 

